This series will cover the construction of a DN iceboat hull from raw materials to finished product as built by Les Druiven and Mike Druiven in Milton during 2021. This is the way we constructed a DN. It is not the only method and, sure, parts could be improved. This is our third build. The first 2 boats have competed in regattas including the NA championship.
For the most part we used small "garage" type wood working equipment in a 10.5 foot by 20 foot garage/shop. You will need, or need to have access to
- thickness planer
- drill press
- small bandsaw
- large bandsaw to resaw boards 8 1/2 to 9 inches wide
- stationary sander
- handheld belt sander (shaping, scarfing)
- handheld palm sander (finishing)
- table saw
- for crosscutting I use a skill saw
- plenty of clutch style bar clamps
- plenty of C clamps
This procedure was used wherever wood is joined to wood. Make sure all the surfaces to be glued together are clean and smooth.
- On hot humid days your epoxy will harden very fast.
- Cover any surface that is not to be glued with wax paper. For instance gluing up the side panel blanks is done on a 14 foot flat workbench covered in wax paper. Aluminum angle used to spread clamping forces also have wax paper between the workpiece and the aluminum.
- Mix enough epoxy to apply a first coat to all the surfaces being joined.
- Next mix another batch of epoxy with 403 and 404 added until you get a paste and apply to all surfaces.
- Apply pressure forcing all surfaces to be glued together with sufficient force to provide good adhesion without cracking or buckling your work. In most cases that means tighten that clamp down hard!
- If no epoxy squeezes out you did not use enough. If some squeezes out you did good. If a pile of epoxy squeezes out you used too much!
- Drips need to be caught or they will ruin a concrete floor or whatever else it lands on.
Part 1 materials
- Sitka spruce rough sawn 5/4 lumber
- Epoxy glue
- West 105 epoxy
- West 207 Hardener
- West 403 filler
- West 404 high density filler
- Disposable nitrile gloves
- Disposable 1" or 2" brushes (cut the bristles short)
- Wax paper (30 lb kraft paper waxed to 43 lb, industrial if you can. You are going to use lots)
We planed the rough sitka to find checks and splits taking it down to 1 1/8 thickness. Next the lumber was cut into 1 3/8 inch wide strips. The strips were planed down to 1 1/4 inch. We wanted 13 foot blanks so strips that were not long enough were scarfed together to make them 13 feet long. The 1 1/8 thickness gives us room to plane down the resawed blanks to 1/4 or 1/8 thickness. The finished sides are 5/8 thick (1/4 + 1/8 + 1/4).
Here are some pics of the scarf jig on the table saw. Our scarfs are 20 inches long.
We put enough wood to make a side panel together dry, mixing up scarf locations so they aren't all in one area and numbered everything. We followed the glue up procedure. After the coat of thickened epoxy is added to the scarfs we used a couple of staples (which get pulled later before planing) to hold the scarfs in position. The angle aluminum is used as a force spreader. Between each length squeezing the boards together with 2 clamps there is an angle and a clamp holding all the boards flat to the table. We need at least 28 bar clamps and 28 x 16 inch lengths of angle aluminum (or force spreading material) for this procedure.
In part 2 I will discuss resawing the glued up side panels and a form to give the hull shape, cutting the top deck profile and adding the bow and stern blocks.
